F-35B Grounding Traced to Crimped Tubing, Pentagon Says

By Tony Capaccio -
Jan 29, 2013

An “improperly crimped” fluid line
was the probable cause of a propulsion-system leak that led the
Pentagon to suspend flight tests of the F-35 fighter’s Marine
Corps version, according to the Pentagon.

The investigation “ruled out any design or maintenance
issues,” Pentagon spokesman Joe DellaVedova said yesterday in
an e-mailed statement. The evidence revealed “a quality
discrepancy” resulting in the crimped line, he said.

Test flights of the Marine version, the F-35B, were stopped
after a pilot aborted a takeoff because of a flaw in the
propulsion system made by the Pratt & Whitney unit of United
Technologies Corp. (UTX) The incident involved a line in the plane’s
fueldraulic system, which saves weight by using jet fuel instead
of the customary hydraulic fluid to lubricate mechanical parts.

The Jan. 18 flight suspension remains in effect, according
to DellaVedova.

Development of the F-35 has been marked by delays and cost
increases. The Pentagon’s $395.7 billion estimate for the total
cost of development and production of 2,443 fighters is a 70
percent increase since the initial contract with Bethesda,
Maryland-based Lockheed Martin Corp. (LMT) was signed in 2001.

The Marine Corps’ F-35B is designed for short takeoffs and
landings on carriers and amphibious-warfare vessels. It’s the
most complex of three models being built in the Pentagon’s
costliest program. The U.K. and the Italian military are also
buying the F-35B.

Additional Units

An audit of quality control records has identified six
additional “non-compliant units” that have been removed from
aircraft and returned to Pratt & Whitney for replacement,
DellaVedova said. The flawed part is only on the Marine Corps
version.

“We have begun the process of removing the suspect” parts
and “we are performing additional X-ray imaging inspections,”
Matthew Bates, a spokeswoman for the Pratt & Whitney unit of
Hartford, Connecticut-based United Technologies, said in a e-
mail.

“The team continues to work diligently toward completing
the investigation and implementing corrective actions with the
supplier,” Bates said. “We anticipate a return to flight”
soon.

The flawed fueldraulic line was made by Stratoflex Products
Division, a unit of Cleveland-based Parker Hannifin Corp. (PH),
according to the Pratt and Whitney statement.

The company “is fully supporting our customers during the
investigation,” Cheryl Flohr, a Parker Hannifin spokeswoman,
said in an e-mail. “Parker team members have been working
alongside since the beginning of the situation.”

‘Corrective Actions’

The companies “have instituted corrective actions to
improve their quality control processes and ensure part
integrity,” DellaVedova said.

The Pentagon’s inspector general has been investigating
quality management for the F-35, including relevant clauses in
contracts, since February 2012.

The review had identified more than 190 findings as of
September as well as four “notices of concern” have been sent
to the Pentagon’s F-35 program office, the inspector general
said in its latest semi-annual report to Congress.